This project is concerned with normal and abnormal speech production, mainly from biomechanical and neuromotor perspectives. The two studies elaborated are concerned with respiratory function and are expanded and enfolded from Research Grant DC-00218 titled "Speech Breathing Kinematics Across the Human Life Span." Following consideration of these two studies, selected other studies are summarized in less detail to provide examples of the type of research that will be carried out during the remainder of the 5-year cycle. These add focus on laryngeal, velopharyngeal-nasal, and oral airway functions in normal and abnormal speech production. For the studies proposed, non-invasive methods will be used. The first study will test the effects of abdominal trussing on speech breathing in individuals with spinal cord injury. Data from this study will impact on strategies for the management of speech breathing disorders in individuals with neuromotor impairments. The second study will document the nature of the emergence of normal speech breathing in infants and young children and provide a data base against which infants and young children with speech breathing disorders can be compared. Applications should extend to various disorders caused by neuromotor dysfunction, including cerebral palsy, poliomyelitis, myasthenia gravis, spinal muscle atrophy, peripheral neuropathy, and muscular dystrophy.